Patent GB-191112852-A (GB)
Title: Improvements in or relating to the Platen-carriage and Shift-key Mechanism of Typewriters.
Inventor: SPIRO CHARLES
IPC: B41J1/14
Filed: 1911-05-29
Granted: 1912-02-29
Abstract: 12,852. Spiro, C. May 29. Paper - carriages; platen-shift mechanism; shift-key actions. - Relates to arrangements wherein the platen is journaled in an auxiliary carriage which has a shift mounting in the main carriage. The main carriage consists of end plates C connected by bars C<2>, C<3> and runners C<1>, which are mounted by balls on a plate B. The auxiliary carriage consists of end plates D connected by bars D<1> D<2> and a rocking bar D<3>. The various sizes of carriage may be built up from the same end plates by substituting bars C', D<1>, &c. of the required length. The auxiliary carriage is mounted on pairs of parallel links D<4>, D<5>, which are respectively mounted in the main carriage on studs d<4> and a rotatable bar D<5X>. The auxiliary carriage is steadied by the engagement of the plates D with grooves in the plates C. The platen spindle E<2> rests in notches in a yoke E on the main carriage and is held to the auxiliary carriage by spring-controlled locking-arms E<3>. The platen may be dismounted by pulling forward the arms E<3> and lifting the spindle off the yoke. The yoke is pivoted on the rod C' and is engaged at the rear by rollers G<1> on a plunger G which is guided in the frame and is pivoted to an arm H<1> on a rock-shaft H, this shaft being formed with arms H<3> which are engaged by lugs H<4> on shift-key levers H<5> arranged at opposite sides of the machine. The auxiliary carriage is partly counter-balanced by a spring D<6>. Sheet feeding and guiding arrangements.- These devices are mounted as a whole on the auxiliary carriage and comprise paper-fingers M mounted on the bar D<1> and a paper-shelf L secured to the rocking bar D<3> and formed with an extension L<1> carrying feed-rollers L<2>. The shelf may be pulled forward against the tension of a spring on the bar D<3> to release the rollers and may be held in the forward position by a . cam-lever L<3>. The fingers M are provided with rollers and are pressed inwards by spiral springs. The fingers may be moved along the bar D<1> for the purpose of holding a narrow strip such as is used in billing. Ink-ribbon mechanism; printing-point indicators. - The ribbon vibrator K<1>, the ribbon spools K, and the line-finder K<9> have a platenshift adjustment of the following character. The vibrator is connected by a link K<2> to a lever K<3>, pivoted at K<4> to the cross-bar of a frame K' which is pivoted at K<6> in a bracket K' and is connected to an arm H<7> on the shaft H. The spools are carried by rods K<10> pivoted to arms H<9> on the shaft H. The line - finder K<9> is secured to a frame K<8> pivoted at K<13> to the frame K<5>. When the shift-key is depressed the shaft H raises the vibrator, the spools, and the line-finder with the platen. The lever K<3> is pivoted at K<12> to a link K" which is connected to the universal bar, the pivot K<12> being in line with the pivots K<6> of the frame K<7> so that the relation of the vibrator to the universal bar is not affected when the platen is shifted. Line-spacing mechanism. - The line-spacing devices are rendered self-adjusting to the platen-shift movements in the following manner. The line-spacing pawl J<1>, Fig. 1, is pivoted to an arm J<3> which is pivoted at J<4> to the auxiliary carriage and is connected by a link J<5> to a bell-crank lever J<6>, which is pivoted on the main carriage and is operated by a line-spacing lever J also pivoted on the main carriage. The pawl is normally held clear of the line-spacing wheel J' by a spring J<13> on the lever J<6>, a spring J<12> being provided for tensioning the pawl towards the wheel. The spaceadjusting stop consists of a cam J<7X> formed with a thumb-piece J‹ and rotatably mounted in a sleeve 14, which is pivoted to swing in the plane of the wheel J<2> on a stud J<8> secured to the auxiliary carriage. When the platen is shifted, the arm J<3> adjusts itself to the link J<5>, the different travel of the pawl under the altered conditions being too slight to affect the number of teeth taken by the pawl. The sleeve J<14> carries a detent-roller J<10> which is releasable by swinging the sleeve on the stud J<8>. The sleeve may be held in the released position by means of a locking-pin J<11>.